There is a Catalytic converter in new Civic.
Infact one of my friends car is in work shop right now getting it cleaned.
The symptoms you mentioned are definately of chowked Converter.
Now you got two options, either to remove it or get it cleaned. What they do is take off the exhaust part having the converter in it. Cut it open just next to converter with a blade. Remove the chowked part with blade and blow high pressure air into it from both sides.
This process solved the issue for my TZ prado and I am getting better mileage and much improved pick
I recommend not to remove it all together
I recommed a workshop in Islamabad if you would like